private void MenuBackRequested(object sender, Windows.UI.Core.BackRequestedEventArgs e)
{
if (PageContent == null)
{
return;
}
// Navigate back if possible, and if the event has not
// already been handled .
if (PageContent.CanGoBack && e.Handled == false)
{
e.Handled = true;
PageContent.GoBack();
}
}
